Is Tom helping his father( )the house?A cleaningB cleanC cleaned
问题描述：
Is Tom helping his father( )the house?
A cleaning
B clean
C cleaned
答
a
答
A cleaning
答
B
help sb do sth
或
help sb to do sth 都可,
后者没有,只有前者,选B,
如果两者都有,则倾向于选前者
这里的Is 现在进行时是用在helping上的,
后面的clean只要考虑help的用法.