-ed or -ing?

I’ve recently noticed a lot of cases where Hong Kong writers are  unsure about — or just wrong about — a particular structure. It can be illustrated by these two sentences:

1) Money invested in the fund attracts interest of 6%.

2) People investing in the fund have access to our expert financial advisors.

In both sentences, the underlined portion is the noun phrase subject of the sentence. What we are interested in is that part of the noun phrase subject that comes after the head noun (i.e. after money & people, respectively). In each case, we have a form of the same verb, ‘invest’, but in (1) we use the -ed form ‘invested’, and in (2) the -ing form ‘investing'. Why? 

The larger question we want to address is this. When we construct a noun phrase made up of a head noun followed by a modifying expression introduced by  a verb form (like sentences 1 and 2 above), how do we know when to use the -ed form of the verb, and when to use the -ing form of the verb?

It is clear that many Hong Kong writers are not sure about this, and consequently I have frequently come across sentences like the following:

• Only components complied with Specification 3.2 may be used. 
• Only figures recording during the sample period have been used in the study.
• Minor injury consequences include those required first-aid treatment only.
• The number of dogs died of natural cause is small during the relatively short period of study when compared to the average life span of dogs (around 10-12 years for pet dogs).

In all these cases, the underlined portion is the noun phrase, made up of the head noun (in blue), and the part that modifies the head noun (in red). And in each case, the form of the verb that introduces the modifying part is incorrect.

A simple rule of thumb may help here. All the phrases in red are giving us information about an action connected with the noun. That action can be of two kinds:

i) an action that the head noun does
ii) an action that is done to the head noun.

Let’s consider our sentence (2), 'People investing in the fund have access to our expert financial advisors.' Is the verb 'investing’ describing an action that the people do, or an action that is done to the people? Clearly it is the former: it is the people who actively do the investment. In other words, the verb form is describing an active situation. We can see that when the relation between the head noun and the verb introducing the following phrase is an active one, we use the -ing form of the verb. Here are some other examples:

• Any person swimming in the reservoir will be prosecuted.  (the person who is actively doing the swimming)
• Dogs running loose may be impounded. (the dogs that are actively doing the running)

Now consider sentence (1), by contrast: 'Money invested in the fund attracts interest of 6%.'  Is the verb ‘invested’ describing an action that money does, or an action that is done to the money? Clearly money cannot actively invest itself, so this must be an example of money having an action done to it. In other words, the relation between the verb form and the head noun is a passive one. In these cases, we have to use the -ed form of the verb, as in the following examples:

• Bags placed here will be removed.  (the bags have not actively placed themselves, so ‘place’ describes a passive relation) 
• The photos displayed on the walls are available for purchase.  (the photos have not actively displayed themselves, so ‘display’ describes a passive relation)

In these passive relations, the correct form of the verb is -ed.

A key point to note here is that a large group of verbs in English, known as intransitive verbs, cannot take passive forms. Intransitive verbs cannot be followed by a direct object and therefore cannot be passivised. That means that when these verbs are used in the structure we are discussing, they must always take the -ing form, never the -ed form.

The injuries resulting from the breakdown were significant. [‘result’ is an intransitive verb and cannot be passivised)
The number of dogs dying of natural causes is small. [‘die’ is an intransitive verb]
Only components complying with Specification 3.2 may be used.  [‘comply’ is an intransitive verb].
​​

​