How do I know if themselves is a reflexive or intensive?

[Nicole Kidman]

English Language Tests, Intermediate level

ESL/EFL Test #172 "Reflexive and intensive pronouns", question 2

Deep-sea divers wear wetsuits to protect ......... under the water.

(a) ourselves
(b) yourselves
(c) themselves
(d) itself

English Language Tests, Intermediate level

ESL/EFL Test #172 "Reflexive and intensive pronouns", answer 2

Deep-sea divers wear wetsuits to protect themselves under the water.

Correct answer: (c) themselves
_________________________

How do I know if themselves is a reflexive or Intensive

Nicole Kidman

[Conchita]

Whenever the verb or pronoun refers back to the subject, it is reflexive.

[Yankee]

.
Reflexive pronouns can be objects of verbs (and prepositions) or they can simply intensify a noun.

Object:

- I know myself very well. --> Myself is the object of the verb, and is also the same as the subject.

- He kept the secret to himself. --> Himself is the object of a preposition and refers back to the subject of the sentence.

Intensifying:

- I myself don't know him.

- He built his house himself.