believe and believe in ?

zyc50

\"To believe X\" means to take whatever X is claiming and think it is
true.
\"To believe in X\" means to have faith and confidence in X's abilities
or qualities.

Slightly different meanings triggered by the use of \"in\".
Adjectives also select different prepositions. For example:
- I am happy with it.
BUT NOT:
* I am happy by it.

- I am happy with him.
- I am happy for him.
BUT NOT:
- I am happy in him.
BUT OKAY:
- I am happy in my job.