不像…那么 / 不像…这么【bú xiàng … nàme / bú xiàng … zhème】

A 不像 B 那么 + adjective means A is not as tall, hot, busy as B. 那么 points at a B that is away from you; 这么 at one that is here, or is the speaker.

It says the same as 没有…那么 and the two swap freely. Like that frame, it takes no 很 before the adjective, and the adjective is the quality B has more of.

• × 他不像我很高 → 他不像我这么高
• × 今天不像昨天很冷 → 今天不像昨天那么冷

Keep the 那么 or 这么. Without it, 他不像我 reads as "he isn't like me", and the adjective has nothing to hang on.

Unlike B

不像 B, followed by a comma and a clause, means "unlike B". The clause says how A is different, and it can be a whole statement rather than one adjective.

With a verb, 那样 or 这样 can stand for "the way B does".