ESL Lesson: Be Supposed To

🎯 Lesson Goal

In English, we use be supposed to when we want to talk about rules, obligations, or things that people expect us to do.

✅ Good pattern: Think of it as a softer way to say "have to" or "should." It usually means someone else gave you the rule.

❌ Common mistake: Do not confuse this with the Spanish verb suponer! In English, the verb "suppose" means "to guess" or "to assume."

Look at how the meaning changes depending on the structure.

Structure	Meaning	Example
be supposed to	Obligation, rule, or expectation.	I am supposed to arrive at 8:00 AM.
was/were supposed to	A past expectation that didn't happen.	I was supposed to call you, but I forgot.
suppose (verb)	To guess or assume (like suponer).	I suppose it will rain later today.

Follow these two main rules to build the sentence correctly.

Always use: Subject + Be + supposed to + Base Verb

✅ Correct: She is supposed to go.

❌ Wrong: She suppose to go.

Because the "d" in supposed and the "t" in to blend together when speaking, many students forget to write the "d".

✅ Correct: We are supposed to wait.

❌ Wrong: We are suppose to wait.

Because of the Spanish verb suponer, Spanish speakers often make transfer errors. Look at these direct translations.

Spanish Idea	English Mistake	Correct English
ES: Supongo que va a llover.	I am supposed that it will rain.	I suppose it will rain.
ES: Se supone que debo trabajar.	I suppose to work.	I am supposed to work.