I apologize Illjadw, so how I know about their ability to speak English. Ukraine does have a decent educational system and those who have been educated after the collapse of the Soviet Union speak English. Senior commanders of the Ukrainian armed forces speak it too. I know because I have met them and asked about it. Their senor commanders have been trained to use the NATO command structure since 2014 and they have been pretty good at it.
How instructors train people speaking another language, its fairly simple. If we take instructors for the Javelin. One instructors educate about 50 Ukrainian instructors and they go out to educate other Ukrainians how to use the weapon. It is not complicated for trained soldiers to learn how to use other weapons, unless you want to use infantry soldiers as tankers or gunners. What takes longer is to educate technicians repair other systems.
How a defender can defeat an attacker. It depends on the terrain. In forest areas and areas with few roads. Use the same MO as how the Finns fought the Soviets, a small force actually defeated a much stronger force. Another example is how the Israelis fought the Syrians on the Golan Heights. When the enemy is losing its cohesion, your own forces can counterattack. Ukraine has a varied terrain so it is up the local commanders to decide to do what.
About the linguistic abilities of the Ukrainians : these are not better than those of the average Germans, French,Belgians, Italians :to speak,understand English depends only on a small part on the educational system,what is decisive is the chance to speak English and this is mostly lacking .
Ask in Belgium,France, etc in English for the directions,the result will be that in 90 % + of the cases,people will be unable to answer you in English .That Ukrainian generals are used to speak English ,does not mean that this is the case for Ukrainian officers,NCO,soldiers .
It is also an exaggeration to say that to defeat an attacker depends on the terrain .Much more important is the strength of both parties and their willingness to commit more resources and their willingness to accept huge losses.
And, counterattacks are not needed .Unless to stop the enemy attacks elsewhere .
The Soviet attacks against AGC in the Winter of 1941-1942 failed,not because of the terrain, not because of the weather but because the Soviets were not strong enough and because the German soldiers obeyed Hitler's order not to retreat .
The Soviets had never any chance to liberate Smolensk,Minsk,Warsaw and to parade in Berlin in April 1942 and the counterattacks of the Ukrainians will not result in the capture of Gomel or Kursk .Because it is not possible and not needed .
Russian attacks did not result in March into their presence on the border with Poland and will not do it this Winter .Besides,there is no need and no possibility for the Russians to go to the border.
A defender can defeat the attacker by remaining defensive . See Verdun .
