[Grammar] The first postage stamp, to be issued on May 1860 in England, was the Penny Black.

[Son Ho]

Goof afternoon, everyone. Could we use a non-defining relative clause replaced by an infinitive? Please help me with this. Thanks in advance.

1. The first postage stamp, which was issued on May 16th 1860 in England, was the Penny Black.
2. The first postage stamp, to be issued on May 1860 in England, was the Penny Black.

 

[emsr2d2]

Sentence 2 is incorrect. When we use "to be" in such a context, it refers to a date in the future.

The new app, to be rolled out on June 4th, sounds very exciting.

Sentence 1 is correct. It could be worded more simply as "The first postage stamp, issued in England on May 16 1860, was the Penny Black". As you can see, "which was" is optional there.

 

[Rover_KE]

Many keen philatelists called Black have called their daughters Penny.

 

[Son Ho]

Sentence 2 is incorrect. When we use "to be" in such a context, it refers to a date in the future.

The new app, to be rolled out on June 4th, sounds very exciting.

How can I distinguish between to infinitive in relative clauses and to infinitive in the future in case both of the two following sentences have the word first ? Does it depend on the comma in the first and second sentence or we have to understand its meaning to decide?

3. The first man to set his foot on the moon was Neil Armstrong. (to infinitive in relative clauses)
4. The first man to step in the room tomorrow is Mr Johnson. (to infinitive in the future or in relative clauses)

 

[jutfrank]

Your sentence 3 does not include a relative clause. The first man to set foot on the moon is a noun phrase, which is the subject of the sentence.

I don't quite understand what's confusing you. Are you just wondering about when infinitives have a sense of futurity and when they don't?

 

[Son Ho]

I don't quite understand what's confusing you. Are you just wondering about when infinitives have a sense of futurity and when they don't?

Yes, I am. I don't really know when to use to infinitives in the future (sentence 2) or in a relative clause reduced (sentence 3).

2. The first postage stamp, to be issued on May 1860 in England, was the Penny Black.
(incorrect because of to infinitive in the future)

3. The first man to set his foot on the moon was Neil Armstrong.
(correct because to infinitive was reduced from the following relative clause)

5. The first man who set his foot on the moon was Neil Armstrong.
(a relative clause goes right after the first man which we can reduce to infinitive)

 

[jutfrank]

Sentence 3 does not include a reduced relative clause. It uses the construction superlative + to-infinitive. Focus your studies on the use of this construction.

We sometimes use to-infinitives to talk about the future. This is a separate grammar point.

If you focus on these two grammar points separately, your confusion will be resolved.