Rely on/upon somebody/something doing/to do something

Dobrý den/Ahoj, tentokráte přicházím s praktičtější otázkou 🙂

Příkladové věty:

RELY ON+ OBJECT+GERUND

• The success of this project relies on everyone making an effort.
• We relied on his sending us money every month.

RELY ON+ OBJECT+INFINITIVE TO

• We relied on him to send us money every month.
• Many working women rely on relatives to help take care of their children.

Co mám za nejasnost? Platí pro „rely on“ nějaké pravidlo z hlediska toho kdy použijeme infinitiv a kdy gerundium? Přímo po „rely on“ je to jasné a bude gerundium. S předmětem je to však jiné, byť verze s infinitivem převládají. Lze někdy gerundium/infinitiv použít bez rozdílu ve významu?

Tuto problematiku jsem začal řešit poté co jsem udělal chybu v testu:

• Matthew can't rely on Alex helping him if something goes wrong.
• Matthew can't rely on Alex to help him if something goes wrong.

Zde by to zaměnitelně použít nešlo, hádám.

Děkuji.

I don't see any „mistake“ in your answer.

• Matthew can't rely on Alex helping him if something goes wrong.
• Matthew can't rely on Alex to help him if something goes wrong.

A: We relied on him to send us money every month. B: We relied on him sending us money every month. C: We relied on his sending us money every month.

A, B and C are all correct and mean the same.

D: Many working women rely on relatives to help take care of their children. E: Many working women rely on relatives helping take care of their children.

D and E are both correct and mean the same.

• I like when people keep their word and I can rely on them doing what they say they would do. (welldoing.org)
• You can rely on them to do what they said they would do … (developingle­aders.com.au)
• I always had to rely on my parents helping me. (bustle.com)
• I always had to rely on my parents to help me.

There may be a preference for using the to + inf construction for a single one-off event in the future, but that's not a golden rule either, so:

• We can't rely on the weather being good for skiing next March.
• We can't rely on the weather to be good for skiing next March.

Děkuji.

Opraven jsem byl v tomto testu, položka číslo 6.

Takže rely on je jedno z těch slovíček, „verb patterns“, kde lze použít (pokud mezi rely on a sloveso vložíme předmět) jak infinitiv tak gerundium, bez toho aniž bych tím změnil význam věty. Zajímavé, nikde o tomto jevu není žádné pojednání, ani na zahraničních fórech toho příliš k nalezení není. Většinou je zmíněno pouze samotné rely on, které může být přímo, bez předmětu mezi, následováno gerundiem, nikoliv infinitivem.

Interestingly, the version apparently marked as a mistake in your test ties in with my comment „There may be a preference for using the to + inf construction for a single one-off event in the future (the one-off event here being "if something goes wrong“).

It's also interesting that forums and grammar books (I checked Swan's ‚Practical English Usage‘ and couldn't find anything suggesting any difference in these two constructions after „rely on“) don't appear to treat the two constructions differently. This suggests to me that for most speakers most of the time, the two constructions (rely on someone to do something and rely on someone doing something) are pretty much interchangeable with no perceptible difference in usage, otherwise the grammar books would have pointed out any such difference.

However, everyone (no matter what language they speak) has their own idiolect and may tend to see a different usage from their own as unacceptable. English, as we know, has no „Academy“ which can decide what is „right“ and what is „wrong“, and English grammar is descriptive, not prescriptive. It explains how people speak, not how they should speak.