Foreigners often make some strange mistakes in Chinese when they study the most difficult language--- ---Chinese. We try to analyze typical sentences to correct these errors.
Yǒu yì zhī niǎo diào jìn gāng.
False: 有一只鸟掉进缸。
Yǒu yì zhī niǎo diào jìn gāng lǐ.
True: 有一只鸟掉进缸里。
“缸”是个表示实体的名词，不能单独用来作“掉进”的宾语。须在“缸”后加上方位词“里”，表示处所。
As a noun denoting entity, 缸 can not be the object of 掉进 just by itself， but ought to be followed by the noun of locality 里， to show location.
