用括号里所给单词的正确形式填空 1,my son isn't at home and he is studying at

用括号里所给单词的正确形式填空 1,my son isn't at home and he is studying at his___（friend ）home
用括号里所给单词的正确形式填空
1,my son isn't at home and he is studying at his___（friend ）home .
2,i can hear someone ___（sing ）in the classroom .
3,he looked out of the window and ___（shout ）to some children .