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Difference between 例如 and 比如.

Hello, quete.
例如更多用于书面语，比如更多用于口语。
例如 is more frequently used in writing while 比如is more colloquial.

例如 and 比如 are almost the same. 例如 sounds more formal and it is often used in formal occasion. When chatting with others, we prefer to say 比如 and it is more natural than 例如. Hope I can help you.

if you are not gonna take a test, they are same. both are ok in daily life

In spoken Chinese, we hardly ever say "例如". However, "比如" is used in both spoken and written Chinese.

"如" and "譬如" are their synonyms and usually used in written Chinese. "譬如" is not used very often, though. That could be because the pronunciation of "譬" is exactly the same as that of '屁'. : )

both is similiar. the slight difference may be that the former is more formal than the latter.