"I am reading the menu."
Translation:Je lis le menu.
"I am reading" is the continuous verbal form the English uses to express that an action is currently in progress at the time the sentence is said or written.
In French, there is no verbal form to express that (you can't say: je suis lisant)
Therefore, if you get "I am reading", you can translate either "je lis le menu" or "je suis en train de lire le menu" which is a specific construction meaning the same continuity as the English continuous present.
- English continuous verbal form: verb BE + verb in gerund form -ing
- French equivalent: verb ÊTRE + en train de + verb in infinitive form.
Unfortunately, "je suis lis" does not mean anything. "I am reading" is the continuous present of verb "to read", to express that the action is in progress at the time we speak. In French, this verbal form does not exist. Therefore, either you translate "je lis" (and you miss the continuity) or you use the expression "en train de + infinitive: "je suis en train de lire" and the continuity is expressed correctly.