stem和stalk有何区别？

stem: [ stem ]

n. 茎,干,船首
v. 堵住,阻止,起源于

词形变化:
动词过去式:stemmed 过去分词:stemmed 现在分词:stemming 第三人称单数:stems

例句与用法:
1. Our ship stemmed on against the current.
我们的船逆流而上。

2. She bought some roses with long stems.
她买了一些枝干很长的玫瑰花。

3. The liner has been refitted from stem to stern.
那艘班轮已经全面整修.

4. A slight curving or circular movement in a stem, as of a twining plant, caused by irregular growth rates of different parts.
转头运动植物茎的轻微弯曲或扭转的生长，象双生树那样，由不同部分的不规则生长速度引起

5. She sat twirling the stem of the glass in her fingers.
她坐在那里用手指捻著玻璃杯的杯颈.

英英解释:
名词stem:

1. (linguistics) the form of a word after all affixes are removed
同义词：root, root word, base, theme, radical

2. a slender or elongated structure that supports a plant or fungus or a plant part or plant organ
同义词：stalk

3. cylinder forming a long narrow part