E_______n_________g________l_____i_________s_______hI __(1)______ dinner when my son ____(2)_____ home.(1):(A) cooked(B) was cooking(2):(A) came(B) was coming并说明理由

E_______n_________g________l_____i_________s_______hI __(1)______ dinner when my son ____(2)_____ home.(1):(A) cooked(B) was cooking(2):(A) came(B) was coming并说明理由
E_______n_________g________l_____i_________s_______h
I __(1)______ dinner when my son ____(2)_____ home.
(1):
(A) cooked
(B) was cooking
(2):
(A) came
(B) was coming
并说明理由

E_______n_________g________l_____i_________s_______hI __(1)______ dinner when my son ____(2)_____ home.(1):(A) cooked(B) was cooking(2):(A) came(B) was coming并说明理由
B;A
我正在做饭时（进行时）,儿子回来了（过去时）.
儿子回来的动作发生在我做饭的过程中,此类题都这么做.
如：I was doing my homework when my mother came back home.

B,A

b a
正在做饭时儿子回来了
儿子是过去回来的，我那时是正在做饭

1.b
2.a
当我的儿子回家时,我正在做饭.

B,A,
我儿子来家的时候，我正在做饭。