Meaning
In this sentence has happened is used to infer what has taken place but still has relevance to the present moment, as opposed to everything that happened which is firmly in the past and is definitely no longer happening. We use has or have + the past participle to describe an action that started in the past and is (or might still be) ongoing or still have relevance to the present moment.
To happen also means to take place or to occur.
CCQs:
Are we talking about something that is in the past which has finished? No
Is it still happening? Possibly
Is it still the same day? Yes Form 3rd person singular present tense of the auxiliary verb to have + the past participle of the regular intransitive verb to happen= has happened.
This structure is the present perfect tense. Pronunciation /hæz hæpənd/ The sentence stress falls as follows (underlined where stress occurs): has happened Has has one syllable, happened has two syllables: has hap-penned The two words are linked and flow together when spoken (shown with the underscore): has_happened Appropriacy Neutral Anticipated problems and solutions
Students may think it is the simple past when they spot the past participle, and therefore think it is an event in the past which has finished. Use the white board to write the form clearly to highlight the tense. Students may struggle to pronounce the ed in happened. Highlight the correct and incorrect pronunciation using the phonemic chart and drill.
Students may say the two words separately with no flow. Use the phonemic chart and stress symbols to emphasise and drill.
2. We can put off sleeping for a limited period. (lexis)
Meaning
To put off means to postpone or delay to a future date or time.
CCQs:
Are we sleeping now? No
Do we want to sleep now? No
When will we sleep? Later
Alternative examples: to put off paying bills, to put off something we don’t want to do now.
Form
To put off
References: Longman Dictionary (online) Swan, Michael. Practical English Usage Oxford University Press, 2002 Parrott, Martin. Grammar for English Language Teachers Cambridge University Press, 2000