Проходим present perfect и past indefinite. 1/ were did you last weekend? go went have gone 2/ i to the seaside 3 years ago. have gone went go 3/ how lucky you this year! was were have been 3/ they always for moscow by plane. have left leave left 4/ we decided at the hotel stay stayed to stay я плохо знаю это правило, не могу объяснить ребенку. , если знаете.

1/ Were did you last weekend? go
2/ I to the seaside 3 years ago. went
3/ How lucky you ... this year! have been
3/ They always for Moscow by plane.  have left (всегда летали) leave (всегда летают) – два варианта подходят
4/ We decided ... at the hotel to stay