I used to translate these for a more technically orientated F1 forum until they started deleting translations that they deemed off topic. Hopefully that won't be the case here.
I can't make out many of the characters. Regarding changes from the 2017 unit, the air filter is bigger. Again the tube from the air filter to the compressor is bigger and of a shallower angle so the airflow is easier. The same is true of the tailpipe (exhaust?)
The first target for the 18 engine was reliability. Although almost all of the parts are new the PU appears very similar to the previous. Combustion is where there is most to gain, but they didn't want to change too much as introducing too many technologies at once as per the previous three years could have resulted in similar reliability issues. I think they mean the 2018 unit started with the 2017 combustion system while other teams developed the combustion systems that were introduced during the season. They aimed primarily for reliability with spec 1 with some performance gains but spec 2 and 3 were more performance orientated. Spec 3 performance gains were far in excess of what was expected and that resulted in problems balancing that with the reliability. In Russia the spec 3 suffered from oscillation issues just after upshifts as the revs dropped. This has been resolved completely and they are confident this problem won't recur for 2019. Oscillation issues don't arise in other Honda PUs in other formula. This is because in a fuel limited formula (ie F1) power is gained by increasing the compression ratio and making the fuel/air ration leaner. The leaner it gets the more unstable the mixture. At about 10-12.5k rpm combustion times are incredibly short and the slightest issue can cause problems. Ideally to convert combustion to kinetic energy most economically the combustion time should be as short as possible but this causes difficulties. Also with seamless shift gearboxes the transition from combustion at the higher revs with the previous gear to the lower revs of the next gear is nearly instantaneous. In other formula there is no fuel flow limitation, the engine operates at lower RPM and seamless shift gearboxes aren't used.
Honda gelled well with STR and the new team allowed Honda to change the air filter, tube to the compressor and tailpipe to improve airflow although this resulted in increased bulk. Also STR provided an intercooler with less loss. So Honda believed merely switching teams allowed them to liberate a little power. STR's attitude was to let Honda do what was required to improve their performance then fit the chassis around it which was different to before. Likewise the 2017 oil tank which caused so many problems was designed in such a way to minimise space use, however the 2018 tank is bulkier which has resolved the previously encountered issues that caused so many problems in 2017 with the MGUH shaft, again thanks to STR being more tolerant of the PU dimensions increasing. McLaren preferred to have the intercoolers on the left while STR prefers them split on both sides, apparently purely a difference of philosophy. The 2017 and 2018 units reflect this difference.
The PU harvests energy in three ways. Via the MGUK during acceleration (sapping some energy off the ICE), during braking and also via the MGUH to the battery. The first two methods are limited to 2MJ per lap, the latter is unlimited. More than half the energy harvested during a typical lap is through the latter method (my note, this is pretty amazing given this technology was only introduced by Honda mid 2017). Apparently efficiency improved from 2017 to 2018 despite a handicap resulting from changing teams due to a difference in gear ratio selection between McLaren and STR. Apparently McLaren prefer shorter gear ratios with the PU operating in a higher rev range while STR prefers longer gear ratios with the PU operating at a lower rev range. Harvesting from a higher rev range is easier and therefore switching to lower operating revs decreased the efficiency, despite this it is still better than in 2017. Energy is deployed largely via the MGUK but with a small amount being used to e-boost the MGUH.
Spec 2 improved combustion, exhaust efficiency and less losses from the water pump. As STR and Honda had not worked with each other before the first spec PU and chassis were developed with large margins of error. The spec 2 was developed with a smaller margin of error as they knew STR's radiator specs more precisely, hence the smaller water pump. Spec 2 was a development of the spec 1, but spec 3 had new technologies including something that they had found that improved performance substantially resulting in a bigger step over spec 2 than spec 2 was over spec 1.
The 2019 unit will be a refinement of the 2018 unit. If there was no MGUH then combustion would simply be made leaner to improve power, but with an MGUH this would result in decreased harvesting so a balance has to be found. Some tracks put more emphasis on ICE performance, others more on MGUH performance so both need to be improved and different balances between the two found for each track. However 2018 has provided new perspectives and has shown that some of the technologies being developed have real potential.