1. Ever since he was a baby, he suffered from a serious illness.
2. Ever since he was a baby, he has suffered from a serious illness.
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Which one is correct? Are both grammatical? Then what is the difference in meaning between them?
The difference between 'suffered' and 'has suffered'?
I think #2 is better. Yes, the helping verb "has" makes the sentence clearer, so there is a difference. In the first sentence, the reader has to stop and put the two clauses together. He suffered from an illness? Oh, since he was a baby, so maybe he still has it. It's very clear in the #2 sentence.
Both sentences are grammatically correct, but there is a slight difference in meaning between them.
The first sentence, "Ever since he was a baby, he suffered from a serious illness," uses the simple past tense "suffered." This indicates that the suffering from the serious illness started in the past and continued until the present or a specific point in the past. It suggests that the person may or may not still be suffering from the illness at present.
The second sentence, "Ever since he was a baby, he has suffered from a serious illness," uses the present perfect tense "has suffered." This implies that the suffering from the serious illness started in the past and is still ongoing in the present. It emphasizes the continued state of suffering up to the time of speaking.
In summary, the difference lies in the aspect of time. The first sentence focuses on the past action of suffering, while the second sentence emphasizes the ongoing nature of the suffering up to the present moment.