问如何阻止语言翻译Api翻译bot框架中的表单流输入

EN

    Code:
    public async Task<HttpResponseMessage> Post([FromBody]Activity activity)
            {
                //trust Webchat &SMS channel
                MicrosoftAppCredentials.TrustServiceUrl(@"https://webchat.botframework.com", DateTime.MaxValue);
                MicrosoftAppCredentials.TrustServiceUrl(@"https://sms.botframework.com", DateTime.MaxValue);

                Trace.TraceInformation($"Incoming Activity is {activity.ToJson()}");

                if (activity.Type == ActivityTypes.Message)
                {
                    if (!string.IsNullOrEmpty(activity.Text))
                    {

                        //detect language of input text
                        var userLanguage = TranslationHandler.DetectLanguage(activity);

                        //save user's LanguageCode to Azure Table Storage
                        var message = activity as IMessageActivity;

                        try
                        {
                            using (var scope = DialogModule.BeginLifetimeScope(Conversation.Container, message))
                            {
                                var botDataStore = scope.Resolve<IBotDataStore<BotData>>();
                                var key = new AddressKey()
                                {
                                    BotId = message.Recipient.Id,
                                    ChannelId = message.ChannelId,
                                    UserId = message.From.Id,
                                    ConversationId = message.Conversation.Id,
                                    ServiceUrl = message.ServiceUrl
                                };
                                var userData = await botDataStore.LoadAsync(key, BotStoreType.BotUserData, CancellationToken.None);
                                var storedLanguageCode = userData.GetProperty<string>(StringConstants.UserLanguageKey);
                                //update user's language in Azure Table Storage

                                if (storedLanguageCode != userLanguage)
                                {
                                    userData.SetProperty(StringConstants.UserLanguageKey, userLanguage);
                                    await botDataStore.SaveAsync(key, BotStoreType.BotUserData, userData, CancellationToken.None);
                                    await botDataStore.FlushAsync(key, CancellationToken.None);
                                }
                            }
                        }
                        catch (Exception ex)
                        {
                            throw ex;
                        }
                        //translate activity.Text to English before sending to LUIS for intent
                        activity.Text = TranslationHandler.TranslateTextToDefaultLanguage(activity, userLanguage);
                        //await Conversation.SendAsync(activity, () => new Dialogs.RootDialog());
                        await Conversation.SendAsync(activity, MakeRoot);
                    }
                    else {
                        await Conversation.SendAsync(activity, MakeRoot);

                    }
                }
                else
                {
                    HandleSystemMessageAsync(activity);
                }
                var response = Request.CreateResponse(HttpStatusCode.OK);
                return response;
            }
            internal static IDialog<object> MakeRoot()
            {
                try
                {
                    return Chain.From(() => new RootDialog());
                }
                catch (Exception ex)
                {
                    throw ex;
                }
            }