【正文】
take care of sb. = look after sb. be sure of / about sth. be sure to do sth. be sure 接句子 Sb./Sth. is / are doing sth. when Sb. / Sth. +do / does sth. Sb./Sth. was / were doing sth. when Sb. / Sth. +did sth. 表示一個(gè)動(dòng)作正在發(fā)生 ,另一個(gè)動(dòng)作又發(fā)生了 . 句型 :was / we