by turns

詞意辨析：

by turns, in turn

這兩個詞組都與turn有關。
by turns: 意思是“輪流地”、“交替地”、“忽而...忽而...”（ one after another； alternately or in rotation）

• We read the poem by turns.
  我們輪流讀這首詩。
• They sang songs by turns.
  他們輪流唱歌。
• He grew pale and red by turns.
  他的臉一會兒紅一會兒白。

in turn: 意思是“依次相繼地”（each in due succession）

• We sang the song in turn.
  我們依照次序唱歌。
• We were summoned in turn to see the judge.
  法官依次召見我們。

英文字典

例句：

1. He gets cheerful and depressed by turns.
   他的情緒高一陣低一陣。
2. We did the work by turns.
   我們是輪流做這項工作的。
3. The shop assistants had to have their days off by turns.
   店員要輪流休息。