Update spi_on_wiznet_ethernet_shields.md

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docs/spi_on_wiznet_ethernet_shields.md

@@ -9,31 +9,29 @@ the hardware SS pin, 53, is not used to select the Ethernet controller
 chip, but it must be kept as an output or the SPI interface won't work.
 
 
-On WIZnet shields pins 11,12, and 13 are **tied up** (by defualt) with the
+On WIZnet shields pins 11,12, and 13 are **tied up** (by default) with the
 corresponding pins on the ICSP header.
 
 ## WIZnet Shield + Arduino Mega
 
-When you assembly a Winznet Shield, 
-e.g [W5500 Ethernet Shield](https://docs.wiznet.io/Product/Open-Source-Hardware/w5500_ethernet_shield),
-on an Arduino Mega, you will have a **contention between pins !!!**  
-e.g. pin 13, which so happen it is the LED_BUILTIN, with the SCLK pin.  
+When you assembly a Winznet Shield (e.g, [W5500 Ethernet Shield](https://docs.wiznet.io/Product/Open-Source-Hardware/w5500_ethernet_shield))
+on an Arduino Mega, you will have a **contention between pins !!!** For example, pin 13, is used for both LED_BUILTIN and the SCLK pin.  
 
 WIZnet have on their shields "SPI Jumpers", which are **mounted by default**:
-- Mount: SPI signals is connected to D11(MOSI), D12(MISO), D13(SCLK) and ICSP 
+- Mount: SPI signals are connected to D11(MOSI), D12(MISO), D13(SCLK) and ICSP 
 connector
-- Not mount: SPI signals is connected to only ICSP connector
+- Not mounted: SPI signals are connected to only the ICSP connector
 
-so, if you wish to use pins 11, 12 and 13 on a Mega setup, you will have to unmount the SPI jumpers.
+So, if you wish to use pins 11, 12 and 13 on a Mega setup for a purpose other than SPI, you will have to unmount the SPI jumpers.
 
 ![W5500 Shield SPI pins](img/W5500_shield_spi_pins.png)
 
 ![W5500 Shield SPI pins](img/W5500_shield_jumper.png)
 
 
 ## Arduino Ethernet Shield 2 + Arduino Mega
-The above mentioned contention is not the case for
-the [Arduino Ethernet Shield Rev 2](https://docs.arduino.cc/hardware/ethernet-shield-rev2).
+
+The above mentioned contention is not the case for the [Arduino Ethernet Shield Rev 2](https://docs.arduino.cc/hardware/ethernet-shield-rev2).
 
 ![sd](img/arduino_ethernet_shield_rev2_schematics.png)