句型转换（将下列陈述句括号内的内容变为强调句）

1.（The  children）often   help   their   parents   do  the   farm  work.

2.  (In  1993),a  tomato  was  developed  that  was  very  different   from  any  grown  before.

3. The  biggest  problem  of   china  farmers  is (the  shortage  of  arable  land).

4. Future  agriculture  should  depend on(high  technology  as  well  as  traditional  methods )

1.It is the children who/that2.It was in 1993 3.that the shortage of arable land

It is the children that often help their parents do the farm work.

It was In 1993 that a tomato was developed that was very different from any grown before.

It is the shortage of arable land that the biggest problem of Chinese farmers is.

It is high technology as well as traditional methods that future agriculture should depend on.

老妈！