Theorie:
Study the information about spelling in the past perfect continuous.
Past perfect continuous (spelling tips for adding the ending -ing to a verb):
| Add -ing to most verbs. | play – playing |  |
| For verbs that end in -e, remove the -e and add -ing. | ride – riding |  |
| For verbs that end in -ie, change the -ie to -y and add -ing. | die – dying |  |
| For verbs with last syllables being stressed 'consonant-vowel-consonant' combinations, double the last letter before adding -ing. | beg – begging |  |
Examples:
They were tired. They had been playing for 2 hours.
My friends were happy. They had been riding horses for 3 hours.