1. finally I could decide on my future job.

2. Finally I could decide my future job.
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Are both grammatical? Do we have to use 'on'? Which one is commonly used?

1. Finally I could decide on my future job.

2. Finally I could decide my future job.
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Are both grammatical? Do we have to use 'on'? Which one is commonly used?

It's better to use 'decide on.' The other expression seems incomplete to me.

Both sentences are grammatically correct, but they have slightly different meanings.

1. "Finally I could decide on my future job."
This sentence implies that after a period of uncertainty or indecisiveness, you have been able to make a decision about the specific job you want to pursue. The phrase "decide on" means to choose or select something from a range of options.

2. "Finally I could decide my future job."
This sentence suggests that you have reached a point where you are able to make a decision about your future job, but it doesn't convey the idea of selecting from different options. The phrase "decide" in this sentence means to make a final choice or determination.

In terms of common usage, the first sentence using "decide on" is more commonly used when talking about choosing a job from multiple options. However, context is essential in determining which version is more appropriate to convey your intended meaning.