a.

1. 不充分的；不適當的；不夠格的；不能勝任的[（+to/for）][+to-v]
   His income is inadequate to pay for it.

   他的收入不夠支付此事的費用。

   He's inadequate for the job.

   他不能勝任那個工作。

   The supply of water is inadequate for the trip.

   所帶的水不夠旅途中用。

adj.

1. lacking the quality or quantity required; insufficient.
2. unable to deal with a situation or with life.