湯姆在磨刀。

Tom is sharpening a knife.

Source: Tatoeba

Sentence Composition

1 湯姆 Tāngmǔ Tom (name)
2 在 zài
  1. to exist; to be alive
  2. (of sb or sth) to be (located) at
  3. (used before a verb to indicate an action in progress)
3 磨刀 módāo to hone (a knife)