Theboysaresittingunderthetree.(对划线部分提问)
___________________________________________
Theboysliketolistentomusicwhentheydo______(they)homework.
Ihavetwogoodpenfriends.OneisanAmerican,______isinEngland.
Sheis______(good)thanAliceatswimming.
About________percentoftheearth'ssurfaceiscoveredwithwater
letus(缩写形式)__________