Употребите пассивные конструкции вместо активных:

a) The students have learned a lot of new English words.

b) They had eaten all the dinner before they finished the conversation.

c) Somebody recommended me this doctor.

d) My sister is packing the things now.

e) You should learn these rules immediately

A lot of new english words have been learned by the students. all the dinner had been eaten before they finished the conversation. this doctor was recommended me by somebody. the things are being packed by my sister now. these rules should be learned immediately.