题干
—You've dropped ________“s” in the word “necessary”.
—Oh, ________letter “s” is doubled.
A：a; a
B：a; the
C：an; the
D：the; the
答案(点此获取答案解析）
C
—You've dropped ________“s” in the word “necessary”.
—Oh, ________letter “s” is doubled.
A：a; a
B：a; the
C：an; the
D：the; the
