按说, 不由得, 截然 and 日趋: Adverbs of Expectation and Change

Pattern

按说/按理 + expected fact ／不由得 + reaction ／截然不同／日趋 + two-syllable word

按说 states what should normally be true; 不由得 marks a reaction you can’t stop; 截然 means “completely”; 日趋 means “more and more each day”.

按说他早该到了，怎么还没来呢？

When to use 按说, 不由得, 截然 and 日趋: Adverbs of Expectation and Change

These adverbs describe how an event relates to what we expect, or how a change happens. 按说 and 按理 (often 按理说) mean “normally, by rights”: they state what should be true, usually before a fact that doesn’t match (按说他早该到了，怎么还没来？). 不由得 means “can’t help, without meaning to” and goes before a natural reaction (不由得笑了). 骤然 is a written “suddenly, abruptly”, often for weather, sounds or mood (气温骤然下降). 截然 means “completely, sharply” and is used in a few fixed combinations: 截然不同, 截然相反. 日趋 means “more and more as the days go by” and goes before a two-syllable word (日趋完善, 日趋方便). 特此 “hereby” ends formal notices: 特此通知.

看到这张老照片，奶奶不由得想起了小时候的事。

Seeing this old photo, Grandma couldn’t help remembering her childhood.

这对双胞胎长得很像，性格却截然不同。

These twins look very alike, but their personalities are completely different.

随着新地铁线的开通，城市交通日趋方便。

With the new subway lines opening, getting around the city is becoming more convenient day by day.

一阵大风吹过，气温骤然下降。

A strong gust of wind blew through, and the temperature dropped sharply.

Common traps

按说 introduces what should normally be true; it usually needs a contrast after it (可是, 怎么…呢).
截然 only combines with a few words like 不同 and 相反: 截然不同, not 截然好.
日趋 is written and needs a two-syllable word: 日趋成熟; in speech, say 越来越.

Targeted drill

Practice this exact pattern before moving on.

经过几年的建设，学校的设施完善

After several years of building, the school’s facilities are becoming more complete day by day

rì qū

Meanings

day by day; increasingly

Fill in the missing piece, then press Enter

When to use 按说, 不由得, 截然 and 日趋: Adverbs of Expectation and Change

Common traps

Targeted drill

Keep this pattern in review.