subtle difference between "be to infinitive" & the simple/past present tense?
John went to Spain for a English course, and there he met Janet. They had been dating for 7 months. Before the end of the course, they got married.

1) John met Janet, whom later became his wife, when he was in Spain learning English.
2) John met Janet, whom was later to become his wife, when he was in Spain leaning English.

In the book of Advanced English Grammar that i am reading, there says "we use "to be infinitive" to talk about 1) future events that can be controlled by people, 2) official/formal arrangement and/or instructions,3) giving orders", now please help me apprehend sentence #2, and also Is sentence #1 ever correct; if yes, what is the difference in meaning between these sentences to you?

thank you

Question

subtle difference between "be to infinitive" & the  simple/past present tense?
John went to Spain for a English course, and there he met Janet. They had been dating for 7 months. Before the end of the course, they got married.

1) John met Janet, whom later became his wife, when he was in Spain learning English.
2) John met Janet, whom was later to become his wife, when he was in Spain leaning English.

In the book of Advanced English Grammar that i am reading, there says "we use "to be infinitive" to talk about 1) future events that can be controlled by people, 2) official/formal arrangement and/or instructions,3) giving orders", now please help me apprehend sentence #2, and also Is sentence #1 ever correct; if yes, what is the difference in meaning between these sentences to you?

thank you

Answer

Apart from the *whom/who issue already pointed out by your earlier reviewer, it seems to me that your advanced English textbook is wrong (or is being misquoted) in what concerns the use of "be to": it can be used to describe future events which are NOT controlled by the partcipants. Both sentence 1 and 2 are correct, but the difference is that if you say "...who was later to become his wife" you introduce the element of Fate: neither John nor Janet knew at the time, nor could possibly predict and control the future evolution of events, but it was their destiny to become husband and wife. That nuance is absent if you just say "...who later became his wife".

Answer

corrections:
1. As fdmaxey said, whom should be who in both sentences.
2. "... reading, there says..." should be "... reading, it says..."

Yes, the usage of sentence 1 is correct.

The second sentence implies that it was already known or assumed that they would marry later. But it's used incorrectly quite commonly by native English speakers in the meaning of the first sentence, where the fact that they marry later is a simple side-note.

NB: When used correctly to imply that it is known or assumed they will marry later, it is in fact unsure if they actually did get married later or not.

Answer

"You are to report at 9 hundred hours." = You must report at 9:00.
"You are to submit a complete description of your activities since entering the country." = You must submit....

One correction:
"...who later became his wife,..."
"...who was later to become his wife..."
'Who' is the subject of the subordinate clause.

Answer

thank you all for the replies, especially for Luis's and Setan's. i think i understand what you two were trying to say, and from MY point of view, Luis's and Sertan's interpretations of "be to infinitive" of my case are "closely" similar. However, i felt more connected to Luis when he quoted "the element of Fate", which makes me feel that, with the use of "be to infinitive", John and Janet's marriage was somehow planned by (let's say) destiny; whereas sentence #1 sounds to give extra information about the two.