Я так поняла, что в первом задании нужно дать множественое число? Если нет - напишите в комменртариях)
a mouse - mice
a piano - pianos
a fox - foxes
a man - men
a butterfly - butterflies
a child - children
1) How old is Mark? - He is 10 years old.
2) What does he do every summer? - Every summer his family and he go on holiday.
3) What is he doing at the moment? - At the moment he is travelling by plane with his family.
4) Why is he happy? - He is happy becuase they are going to America.
5) What does he want to be? - He wants to be a pilot.