Question

---How old is your grandpa this year , Tom ?
--- ___________. And we are planning a party for his ________ birthday.

A．ninety ; ninety	B．ninetieth ; ninetieth
C．ninety ; ninetieth	D．ninety ; ninetieth

Answer 1

C

解析試題分析：句意：湯姆，你的爺爺今年多大年紀了？九十。我們為他的九十歲生日正籌劃晚會。ninety90歲，年齡用基數詞；his ninetieth birthday他的九十歲生日，要用序數詞。故選C。
考點：考查數詞。