update doc

Signed-off-by: Nshawn_he <shawn.he@huawei.com>

en/readme/request.md

+# Upload and Download Subsystem
+
+## Introduction
+
+The upload and download subsystem provides upload and download capabilities for applications, including creating, removing, suspending, and starting upload and download tasks, and subscribing to the task progress and result.
+
+
+## System Architecture
+
+**Figure 1** Architecture of the upload and download subsystem
+
+
+![](figures /architecture-of-the-upload-and-download-subsystem.png "Architecture of the upload and download subsystem")
+
+## Directory Structure
+
+The source code of the upload and download subsystem is stored in the **/base/request** directory.
+
+The directory structure is as follows:
+
+```
+/base/request/request
+├── common                   # Common classes such as constants and logs
+├── figures                  # Architecture diagram
+├── framework                # Framework layer
+│   └── js                      # JS APIs that are parsed to NAPIs
+│   └── native                  # Client implementation
+├── services                 # Upload and download service implementation.
+│   └── sa_profile              # System service configuration files
+│   └── etc                     # Process configuration files
+└── test                     # Test cases
+```
+
+## Repositories Involved
+
+[request_request](https://gitee.com/openharmony/request_request)

en/readme/system-time.md

+# Time and Time Zone Subsystem
+
+## Introduction
+
+ The time and time zone subsystem provides OpenHarmony with the capability of managing the system time, time zone, and timing.
+
+-   **Time and time zone management**
+
+    Manages the system time and time zone in a unified manner, including setting and obtaining the system time, date, and time zone, and obtaining the system startup time.
+
+-   **Timing management**
+
+    Provides the system timer capability, including creating, starting, stopping, and destroying timers. There are three types of timers: system startup timer, system time timer, and wakeup timer.
+
+
+## System Architecture
+
+**Figure 1** Architecture of the time and time zone subsystem
+
+
+![](figures/architecture-of-the-time-and-time-zone-subsystem.png "Architecture of the time and time zone subsystem")
+
+## Directory Structure
+
+The source code of the time and time zone subsystem is stored in the **/base/time** directory.
+
+The directory structure is as follows:
+
+```
+/base/time/time_service
+├── etc                      # Process configuration files
+├── figures                  # Architecture diagram
+├── framework/js/napi        # JS APIs that are parsed to NAPIs
+├── interfaces/inner_api     # APIs provided for external systems
+├── services                 # Service implementation
+│   └── profile              # System service and process configuration files
+└── utils                    # Utilities, for example, log utility
+```
+
+## Repositories Involved
+
+[time_service](https://gitee.com/openharmony/time_time_service)