Concept:
• The smile as a psychological mask used to conceal pain.
• The contrast between external appearance and internal emotional turmoil.
Step 1: Analyze the emotional state of the poet
Kamala Das is overwhelmed with the "familiar ache" and the childhood fear of losing her mother.
As she sees her mother's pale, "corpse-like" face, she is filled with immense sadness and anxiety about her mother's impending death.
Step 2: Explain why she repeats the smile
The repetition of "smile and smile and smile..." suggests a desperate, hollow attempt to hide her true feelings.
It serves as a mask to reassure her mother that she will see her again, while also acting as a mechanism for the poet herself to cope with the unbearable pain of separation.