Final answer:
The sentence 'The receptionist welcomed the guests and asked them to fill in the form uses Simple Past tense for the verbs 'welcome' and 'ask' because they refer to completed actions in the past.
Step-by-step explanation:
The verbs 'welcome' and 'ask' in past tense become 'welcomed' and 'asked'. So, the correct sentence should be: 'The receptionist welcomed the guests and asked them to fill in the form'.
The Simple Past is used to talk about actions or situations completed in the past. On the other hand, the Past Progressive expresses an action in progress at a certain point in the past.
Answer: 'The receptionist welcomed the guests and asked them to fill in the form'.
Learn more about Past Tense