1. Ten years ago, I went to the tropics for the first time.
    十年前我第一次到热带去。

2. This plant only grows in the tropics.
    这种植物只生长在热带地区。

1. 热带：tropic 热带 [助记]热带(tropic)拿花(r)做主题(topic)[助记]死(se)人(ren)都很安静口诀:不吹动(blow),飞流动(flow),哥发光(glow),洞中空(hollow)弟弟转业退伍以后,他的工作被拖延(delay)了,弟弟很伤心,所以他和隔壁比赛边飞边吃的技术(feat),

2. 回归线：reefer---海军准尉 | tropic---回归线 | yankee---北方佬

3. 回归线热带的：trigger 引发;引起;板机 | tropic 回归线 ;热带的 | underlie 位于...之下;成为...的基础

4. 向性的：tropholytic layer 營養分解層 | tropic 向性的 | tropical 熱帶的

1. either of two parallels of latitude about 23.5 degrees to the north and south of the equator representing the points farthest north and south at which the sun can shine directly overhead and constituting the boundaries of the Torrid Zone or tropics

1. of weather or climate
    hot and humid as in the tropics

    e.g. tropical weather

    Synonym: tropical

2. relating to or situated in or characteristic of the tropics (the region on either side of the equator)

    e.g. tropical islands
           tropical fruit

    Synonym: tropical