I am having problem understanding the difference between んじゃないかと思った and
んじゃないかと思う。

As for んじゃないかと思った, I found the following examples:"忘れているんじゃないかと思った" and
"間に合わないんじゃないかと思った"。

Moreover, in regards to んじゃないかと思う, I found these two examples:
"断れたんじゃなかったかと思いますが" and "慎重なんじゃないかと思う".

To be honest, i found myself unable to translate these sentences and thus
understanding the grammar behind them. Could you explain them to me?

I know かと思った that expresses that one thought/ was afraid that something would
happen, but eventually it did not. However, despite being apparently similar
they seem to hold a different meaning and usage.
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2018-11-21T19:04:25.013
62974
2019-12-16T21:02:55.403
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question
grammar
The use and difference between んじゃないかと思った　and　んじゃないかと思う
思った is past tense, whereas 思う is present tense. 思う would be used when
communicating what you currently think/feel, whereas 思った would convey what you
thought at the time of the subject in question. Expressing fears that turned
out to be unfounded is indeed a common use of 思った, but it's hardly limited to
that.
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2018-11-21T19:33:46.640
62977
2018-11-21T19:33:46.640
29876
62974
answer
As it has already been stated the former is in the past tense whereas the
latter is in the present/future tense.

> 忘れて/いる/ん/じゃない/か/と/思った : (I) thought (思った) isn't it (じゃないか) that (ん) (he)
> has/forgotten (忘れて/いる) : I wondered if he had forgotten it.

You can also understand it like this:

> 「間に合わないんじゃないか」と思った : (I) thought (と思った) "is it not that I will not make it
> in time ?". : I wondered if I would make it in time

Present tense is the same thing, but you understand it as "I think" instead of
"I thought". You would be better off learning each part individually instead
of trying to understand んじゃないかと思った as a whole expression.
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2018-11-21T20:01:54.267
62978
2018-11-21T20:01:54.267
62974
answer