YOU SAID:

i only got four hours of sleep last night.

INTO JAPANESE

私は昨夜4時間の睡眠しか取れなかった。

BACK INTO ENGLISH

I only got four hours of sleep last night.

INTO JAPANESE

私は昨夜4時間しか眠れなかった。

BACK INTO ENGLISH

I could only sleep four hours last night.

INTO JAPANESE

私は昨夜4時間しか眠れなかった。

BACK INTO ENGLISH

I could only sleep four hours last night.