When did Mary’s family went to Ho Chi Minh City?

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Last summer, Mary went to Ho Chi Minh City with her parents. It took them eighteen hours to go there by bus. They stayed in a big hotel. It was clean and comfortable.

On the first day, they visited Nha Rong Harbor, Reunification Palace and some other places of interest. On the second day, they visited Cu Chi Tunnels. Finally, they went to Vinh Nghiem pagoda and the Duc Ba Cathedral. After three days in Ho Chi Minh City, they went to Hue to visit some citadels there. They really enjoyed their stay in Viet Nam.

When did Mary’s family went to Ho Chi Minh City?