 Complete the following phrase:  As Japans invasion loomed, Lin Huiyin and her husband had to cut-short their promising restoration work of Beijings cultural heritage sites in 1937 and abandoned their now famous courtyard residence in Beijing to flee southward along with personnel and materials of the Architectural Department of Northeastern University; their exodus lead them and their children to temporary settlements in the cities of Tianjin, Kunming, and finally Lizhuang in 1940. It was in Lizhuang where the bedridden Lin Huiyin, suffering from tuberculosis, was told of her younger brothers martyrdom while serving as a combat aviator in the air force in the 