There are many adjustments that missionaries make when they engage a new culture. Understanding the challenges faced by new missionaries will encourage you to pray faithfully for the missionaries when they leave for the field.
"Third Culture Kids" is helpful book for local church leaders and those interested in understanding and ministering to missionaries as they come home on furlough.
Here are a couple of excerpts:
"The first day after arrival, we busily engage with all we meet, feel excitement that we can actually answer the greetings in this new language we tried to study before we came, and all seems well. We think, “What fun!” A few more days pass, however, and things aren’t quite as exciting. We don’t like not knowing how to get to the store on our own because we haven’t learned yet how to drive on the “wrong” side of the road, we’re tired of not being understood past simple greetings by those around us, and we wish we could go “home”- back to where we knew how to function and where we fit. This is the flight stage.
Soon, however, we get tired of feeling so useless or out of place and begin to get angry. After all, we used to fit. We were competent individuals in our last home, so it can’t be our fault that we feel so lost and insecure, so we begin to blame
everything and everyone in this new location for our discomfort. If they would only do things “right” (meaning the way we are used to doing them), everything would be fine. Internally, and sometimes externally, we begin to fight with the way things are being done here- perhaps even becoming angry at our mentor who is doing his or her best to teach us these new ways.
Knowing that these reactions might happen doesn’t necessarily stop them, but, again, knowledge helps us at least make more appropriate choices. In this case we might choose not to be quite so vocal about all we despise in our new location.
These are moments we need to remind ourselves that entry also takes time, to remember that six months from now we can presume that somehow we will have learned to drive here, discovered where the stores are for the things we want to buy, and most likely made new friends by then."
It is important that new missionaries have a support team in the homeland praying for them and encouraging them to persevere.