Using c'est

Question

HI,I forget what lesson in A1 I saw this and now I can't find it. But one sentence has c'est un Vieux sac for it's an old bag but the second one is c'est un vieil home for he's an old man. My question is why is c'est for he is or she is shouldn't it be il/Elle est?ThanksNicole

Accepted Answer

Nicole, “ c’est un …” is correct in both your examples. 
The attached lesson covers this. You might like to look at the other links for further discussion too. 
In a nutshell, you will (almost) never use ‘il/elle est’ followed by article/determiner-noun - that will (almost) always need ‘c’est’. 
https://progress.lawlessfrench.com/revision/grammar/c-est-vs-il-elle-est-saying-it-is-she-is-he-is 
https://www.frenchtoday.com/blog/french-grammar/cest-versus-il-elle-est/
 https://www.lawlessfrench.com/grammar/cest-vs-il-est/

Answer

As a good rule of thumb: if the verb is est, use c'est.