根据句意和汉语注释，写出单词的正确形式。

小题1:Though my grandma is in her ___________ ( 九十), she does housework every day.

小题2:He is rich, he still lives a ______（简朴的）life than most people.

小题3:We don’t know whether the bicycles are the _____________( 推销员)

小题4:People need to buy tickets before _________(进入) the cinema.

由于酚醛胶耐腐蚀性较好，易变形老化，适用于腐蚀性较大场所的是（）。

A.电线管

B.焊接钢管

C.硬塑料管

D.半硬塑料管