湯姆幫不了，只能笑笑。

Tom couldn't help but smile.

Source: Tatoeba

Sentence Composition

1 湯姆 Tāngmǔ Tom (name)
2 幫 bāng
  1. to help
  2. to assist
  3. to support
  4. for sb (i.e. as a help)
  5. hired (as worker)
  6. side (of pail, boat etc)
  7. outer layer
  8. upper (of a shoe)
  9. group
  10. gang
  11. clique
  12. party
  13. secret society
=3 不了 bùle no thanks (used to politely but informally decline)
=3 不了 bùliǎo
  1. (as a resultative verb suffix) unable to (do sth)
  2. (pattern: {verb} + 个 ge + ~) without end; incessantly
4 只能 zhǐnéng
  1. can only
  2. obliged to do sth
  3. to have no other choice
5 笑笑 xiàoxiào
  1. laughing or smiling; (the act of) laughter or smiling
  2. laughing, smiling